2 tablespoons grapeseed oil or other mild vegetable oil
1 tablespoon extra-virgin olive oil
1/4 teaspoon Asian sesame oil
Freshly ground pepper
5 ounces baby spinach (8 loosely packed cups)
1 medium bunch watercress, tough stems discarded
2 plums, cut into 1/2-inch wedges
1 crisp, tart apple—peeled, halved, cored and cut into 1/2-inch wedges
3/4 cup shredded Gruyère cheese (about 2 ounces)
Preheat the oven to 350°. In a small saucepan, combine the walnuts, sugar and water; bring to a boil, stirring, until the sugar dissolves. Cook over moderate heat, stirring, for 5 minutes. Using a slotted spoon, transfer the walnuts to a pie plate and sprinkle lightly with salt. Bake for 7 minutes, or until the nuts are fragrant and lightly caramelized. Let cool.
In a small bowl, whisk the vinegar, orange juice, grapeseed oil, olive oil and sesame oil; season with salt and pepper.
In a large bowl, toss the spinach with the watercress, plums, apple and Gruyère. Add the dressing, season with salt and pepper and toss. Scatter the walnuts on top and serve.